1. Field of the Invention
The invention relates generally to the use of O-ring seals, typically formed from elastomer, as shear members. In particular aspects, the invention relates to devices that utilize O-rings as shear members to resist the movement of an axially sliding sleeve.
2. Description of the Related Art
There is a variety of tools and devices used within a wellbore that incorporate sliding sleeves, or arrangements where one tubular member is slidably moved with respect to another tubular member to accomplish some function, such as actuation of a valve or a releasable disconnect. Traditionally, shear pins or other frangible members have been used to releasably secure these components together until it is desired to cause them to slide.
However, the use of frangible members to hold sleeve components together is problematic where the components are subject to high vibration. Vibration can rupture a frangible pin, thereby prematurely releasing the connection that holds the sleeve members together. This results in an undesired activation of the tool. One example of a tool that is normally subjected to high vibration during use is a coiled tubing shear release joint. These tools are used to provide a selective separation point in a continuous length of coiled tubing. The release joint may be activated by shearing of a shearable member, such as a frangible shear pin, to allow separation of release joint components. However, substantial vibration occurs during normal operation of coiled tubing production, and this vibration might cause the shear pin to fail prematurely, thus undesirably activating the release joint.
The present invention addresses the problems of the prior art.